Tube-bending machine



v. P. SCOTT 3,385,092

4 Sheets-Sheet 1 INVENTOR. Vicfior P. 800% TUBE-BENDING MACHINE 5 lliiMay 28, 1968 Filed Jan ATTORNEYS May 28, 1968 v. P. sco'r'r 3,385,092

TUBE-BENDING MACHINE Filed Jan. 5, 1966 4 Sheets-Sheet 2 B-cyl cyI-2INVENTOR. VicfiorP. Scotk BY 9m 3W8 W A'I'I'ORNEYS May 28, 1968 v. P.SCOTT TUBE-BENDING MACHINE 4 Sheets-Sheet 4 Filed Jan.

INVENTOR. VicwrP. Scott 9m, AM W Y B cm on Q- 9. mm T1 18 AITORNEYSUnited States Patent 3,385,092 TUBE-BENDING MACHINE Victor P. dcott,Canton, Ohio, assignor to Macomber, Incorporated, Canton, ()hio, acorporation of Ohio Filed Jan. 5, 1966, Ser. No. 518,893 16 Claims. (Cl.72-381) The invention relates to the bending of tubes, rods and thelike, and more particularly to an apparatus designed for bending steeltubes into zig-zag shape, to form the webportion of the well knownMacomber fabricated steel joist, beam and girder, of the general typedisclosed in Macornber Patent No. 2,457,250, issued Dec. 28, 1948.

Such fabricated steel structural members comprise a zig-zag or revcrselybent web member welded at alternate bends to top and bottom chordmembers, such points of welding being coincident with the panel pointsof the joist or other fabricated structural member.

Various types of apparatus have been designed for bending tubes, rods,bars and the like for forming such web members, but prior to the presentinvention no entirely satisfactory mechanism has been provided for thepurpose.

One such apparatus is relatively expensive to construct, comprising aplurality of slide members, slidable upon a main frame relative to eachother in order to perform the bending operation. Another of thesemachines comprises a heavy complicated apparatus, including large camcylinders for operating bending levers, jaws and the like to bend theweb member.

It is not known that any of such machines is in commerical use, andunder present practice this bending of web members is performedmanually, which is a slow, tedious and expensive operation.

As such fabricated structural members are made in lengths up to sixtyfeet, the web member is very difficult to handle after the first fewbends have been formed therein, and it is very difiicult to maintainuniform bends throughout the length of the web members.

The primary object of the present invention is to provide a relativelysimple, inexpensive machine to bend a tube or the like reversely to forma successive series of oppositely directed Vs to produce a zig-zag bentweb member for use in a prefabricated steel joist or the like.

Another object of the invention is to provide an apparatus of thischaracter in which a length of tube or the like is continuously advancedand bent into zig-zag form by a series of pneumatic cylinders controlledby solenoidoperated air valves.

A further object of the invention is to provide such a tube-bendingapparatus in which the pneumatic cylinders are automatically operated inproper sequence by fourway air valves, each operated by two solenoids.

A still further object of the invention is to provide a tube-bendingapparatus of the character referred to in which a tube or the like isclamped by a longitudinally immovable die and a die upon alongitudinally slidable plate, toggle levers being pivotally connectedto each other and to a transversely movable bending die at one end, onelever being pi-votally connected at its other end near thelongitudinally immovable die, and the other lever being pivot-allyconnected at its other end to the slidable plate.

Another object of the invention is to provide a tubebending apparatus ofthis type, in which one of the toggle levers has a longitudinal slot atthe pivotal connection to the bending die.

Still another object of the invention is to provide such a tube-bendingapparatus in which the bending die is connected to the piston rod of atransversely located pivoted pneumatic cylinder, and in which a pivotedpickup link is provided for engaging the pivot pin of the toggle leversand swinging said cylinder upon its pivot.

3,385,992 Patented May 28, 1968 'ice The above and other objects,apparent from the drawings and following description, may be attained,the above described difficulties overcome and the advantages and resultsobtained, by the apparatus, construction, arrangements and combinations,subcornbinations and parts which comprise the present invention, apreferred embodiment of which, illustrative of the best mode in whichapplicant has contemplated applying the principle, being set forth indetail in the following description and illustrated in the accompanyingdrawings, in which:

FIG. 1 is a side elevation of a web-bending machine embodying theinvention, showing a length of tube or the like inserted into themachine and advanced to the position of the first bend;

FIG. 2 is a similar view showing a subsequent bending operation;

FIG. 3 is a fragmentary sectional elevation, showing the parts in theposition of FIG. 2;

FIG. 4 is a transverse section, on a larger scale, taken on the line4-4, FIG. 1;

FIG. 5 is a fragmentary section on the line 5-5, FIG. 4, showing thegripping dog for feeding the tube or the like forward;

FIG. 6 is an enlarged fragmentary section on the line 6-6, FIG. 1;

FIG. 7 is an enlarged transverse section on the line 7-7, FIG. 2,showing the clamp upon the sliding plate;

FIG. 8 is a fragmentary rear elevation taken on the line 8-8, FIG. 7,showing the adjustable pivot for one of the toggle levers;

FIG. 9 is an enlarged transverse section taken on the line 9-9, FIG. 2;

FIG. 10 is an enlarged transverse section on the line 10-10, FIG. 2;

FIG. 11 is a fragmentary section on the line 11-11, FIG. 10;

FIG. 12 is a fragmentary section of the toggle levers and portions ofthe bending cylinder and piston rod after making a bend and starting toretract;

FIG. 13 is a similar view in the fully retracted position of the bendingcylinder;

FIG. 14 is a diagrammatic view of the pneumatic system including thepneumatic cylinders and the solenoid valves which actuate the cylinders;

FIG. 15 is a schematic view of the cylinders and switches; and

FIG. 16 is a schematic wiring diagram.

Referring now more particularly to the embodiment of the inventionillustrated in the drawings, in which similar numerals refer to similarparts throughout, as indicated in FIGS. 1, 2, 14 and 15, the machine isoperated by a series of pneumatic cylinders including the feed cylinderF-cyl, the bending cylinder B-cyl, a first clamping cylinder cyl-l, andtwo cooperating clamping cylinders cyl-2 and cyl-3.

The apparatus may include a table 4, supported at suitable height abovethe fioor as by uprights 5. Above this table is provided a framework,indicated generally at 6, which supports the feed cylinder F-cyl inhorizontal position.

The piston rod 7 of the feed cylinder is connected at its forward end toa rigid arm 8 upon a slide member 9 slidable upon the horizontal guiderods 10 supported horizontally in brackets 11 upon the frame 6.

A horizontally disposed sleeve 12 is rigidly connected to the slidemember 9, as by the arm 13, and on the forward end thereof is located abracket 14 upon which is pivoted as at 15 a dog 16 having a serratedlower end 17 and having a weighed arm 18 rigidly connected to itsforward side to urged the same downwardly.

Upon the frame 6 is also supported the vertically spaced horizontalguides 19 between which is horizontally slidably mounted the slidingplate 20. Upon the sliding plate is mounted a clamp comprising a grooveddie 21 and a bracket 22 having a horizontal foot 23 at its lower endlocated above the top of the grooved die 21 and so lined up with thesleeve 12 on the slide member 9 that a tube, rod or the like, asindicated at T, inserted through the sleeve 12 will be lined up with thedie-clamp 21-22, so as to be received between the groove of the die 21and the foot 23 of the bracket 22.

Mounted upon the sliding plate 20 are two limit switches indicated atSW-l and SW-Z. These may be limit switches of the type made by AllenBradley Company. The switch SW-2 is adapted to be operated by a pair ofadjustable stops 24 and 25 supported from the frame 6.

The bending cylinder B-cyl is pivotally connected at its upper end as at26 to an upright support 27. The piston rod 28 of the bending cylinderB-cyl is pivotally connected to a pair of toggle levers 29 and 30. Theopposite end of the toggle lever 29 is pivotally connected as at 31 tothe sliding plate 26 and the opposite end of the toggle lever ispivotally connected to a stationary support such as the bracket 32,which may be mounted upon the upright 33. The toggle lever 30 may beprovided with a slot 34 through which is located the pivot pin 35 whichconnects the toggle levers to the piston rod 28 of the bending cylinderB-cyl.

In order that the toggle levers 29 and 31) may be adjusted in length soas to bend tubes or the like into web members of different depths,sleeves 36 may be slidably adjustably mounted upon the ends thereof, asbest shown in FIG. 12, being held in adjusted position as by set screws37 in the sleeves for selective engagement in desired notches 38 in theadjacent edges of the levers 29 and 30. The pivot pins 31 and 31 aremounted upon the sleeves 36 for pivotal connection to the sliding plate20 and to the stationary bracket 32, respectively.

A picloup link 39 is pivoted as at 40 upon the upright 27, below thelower end of the bending cylinder B-cyl, and is provided in its free endwith a notch 41 for a purpose to be later described.

Normally, the pick-up link 39 rests by gravity upon the stop 42 upon theupright 27 or other permanent portion of the apparatus. A groovedbending die 4-3 is welded or otherwise rigidly attached to the head 44upon the lower end of the bending cylinder piston rod 28.

As best shown in FIG. 9, the cylinder cyl-2 is pivotally mounted invertical position upon a bracket 45 mounted upon the upright 33 or otherstationary portion of the apparatus as by the pivots 46.

The lower end of the piston rod 47 of the cylinder cyl-Z may bepivotally connected, as indicated at 48, to a bifurcated member 49,welded or otherwise rigidly con nected to a vertically slidable member50 slidable within the guideways 51. The lower end of the verticalsliding member 50 is curved forwardly and downwardly as indicated at52in FIG. 3.

The guideways 51 may be mounted upon a bracket plate 32 rigidlyconnected to the upright 33 or other stationary portion of the apparatusand a laterally inclined bracket 54 is rigidly connected thereto andextends horizontally outwardly therefrom to support the cylinder cyl-3.

To mount the cylinder cyl-3 upon the inclined bracket 54 two spacedblocks 55 may be welded or otherwise rigidly attached to the undersideof the bracket 54 and an inverted U-shape bracket 56 is welded orotherwise rigidly attached to the blocks 55. The cylinder cyl3 ispivotally mounted between the lower ends of the arms of the U-shapebracket 56 as indicated at 57.

The piston rod 58 of cylinder eyl-3 is pivotally connected, as at 59, toOne arm of a bell-crank lever 60, pivoted at 61 upon a block 62 slidablein guideways 63 and spring-loaded as by the coil Spring 64, one end ofwhich engages the sliding block 62 and the other end of which is locatedin the spring housing 65.

A disc-like die 66 is rigidly mounted upon the other arm of the bellcrank lever 60 for cooperation with the lower end portion 52 of thevertical sliding die member 50 to clamp a tube or the like therebetweenas will be later described.

The cylinder cyl1 is pivotally mounted, as indicated at 67, between thearms of a U-shape bracket 68 welded or otherwise rigidly attached to thespaced blocks 69 which are welded or otherwise permanently attached tothe table 4 or other stationary portion of the apparatus.

The end of the piston rod 70, of cylinder cyl1, is pivotally connected,as at 71, to one arm of a bell crank lever 72 which is pivoted at 73upon a block 74 slidable in guideways 75. Sliding block 74 isspring-loaded by a coil spring 76, one end of which bears against thesliding block 74 and the other end of which is located in the springhousing '77 which may be mounted between the spaced blocks 69.

A disc-like die 78 is fixed upon the other arm of the bell-crank lever72 and cooperates with the upper curved end 79 of the stationary diemember 80 as will be later described in detail.

Referring now more particularly to FIG. 14, which is a diagrammatic viewof the pneumatic system in which the cylinders are located, the pipe 81receives air under pressure from any suitable source. A pipe 82 leadsfrom the air supply pipe 81 to a four-way double-solenoid valveindicated at SVB. This may be the type of double-solenoid pilot-operatedvalve sold under the trademark Speed King by Bellows-Valvair Division ofInternational Basic Economy Corporation of Akron, Ohio. The solenoids onthis valve are indicated in FIG. 14 at 1 and 2 and are indicated on thewiring diagram, FIG. 16, at SVA-1 and SVA-2, respectively.

Pipe 83 leads from the four-Way solenoid valve SVB to the lower end ofthe bending cylinder B-cyl, and pipe 84 leads from the upper end of thebending cylinder to the four-way valve SVB, from which pipe 85 exhauststo the atmosphere.

Air pipe 81 is also connected to the four-way solenoid valve indicatedat SVA, which is similar to the valve SVB and is provided with thesolenoids 1 and 2 indicated in FIG. 16 as SVB-1 and SVB-2, respectively.

Pipe 86 leads from valve SVA to the forward end of feed cylinder F-cyl,and pipe 87 leads from the rear end of the feed cylinder and isconnected, by pipe 88, to the four-way valve SVA, and by pipe 89 to thelower end of cylinder cyl-2, by pipe 90 to the forward end of cylindercyl-3, and by pipe 91 to the forward end of cylinder cyl-l.

Pipe 92 leads from the rear end of cylinder cyl-l to pipe 86 and isconnected to pipe 93 leading from the rear end of cylinder cyl-3, and topipe 94 leading to the upper end of cylinder cyl-2. Pipe 95 leads fromthe solenoid valve SVA to the atmosphere.

Referring now to FIG. 16, SW4 indicates a selector switch which may bemade by Allen Bradley Company. PR indicates a proximity switch, which isa micro switch, and PR1 the contacts in switch PR. CR indicates acontrol relay and CR1 and CR2 the contacts in relay CR. PBl, PB2, PB4and PBS indicate push buttons for initial positioning of material. PBSand PB6 indicate push buttons for manual operation and emergency.

A forwardly and upwardly inclined guide track 96 may be provided forguiding the lower bends in a web member to the die member 80 and ahorizontal guide track 97 may be located beyond the die member 80 forguiding the bent web members out of the machine.

On each side of the die member 80 is an upright 98 to the upper ends ofwhich is connected a horizontal rod 99 so as to hold the partially bentweb W in upright position between the back plate 100 and the horizontalrod 99, as best shown in FIG. 10.

In the operation of the apparatus, a tube or the like, as indicated atT, is manually inserted through the horizontal sleeve 12 and pushedforwardly until the forward end thereof is received between the grooveddie 21 and the foot 23 of the bracket 22. The serrated lower end of thedog 16 will automatically engage the top of the tube as best shown inFIG. 5. The tube is thus clamped automatically for forward movement withthe sleeve 12. Switch SW4 is then closed turning on the circuit. Thenpress the push button PBS (manually) to start the whole cyc e.

This opens the cylinders cyl-l, cyl-Z and cyl-3 and operates the feedcylinder F-cyl to feed the tube forward until the front end of the tubeis located at the point of first bend, namely, between the verticallysliding die member 50 of the cylinder cyl-2 and the disc-like die member66 of the cylinder cyl-3.

At the same time switch SW1 is triggered by slide member 9 on piston rod7. Then through SVAl cylinders cyl-l, cyl-Z and cyl-3 are closed. Thisclamps the forward end of the tube between the cylinder sliding die 50of cyl-2 and the disc-like die of cylinder cyl-3.

At the same time the feed cylinder F-cyl is operated by air admitted tothe forward end thereof to retract the piston rod 7 thereof returning itto the initial position. As piston rod 7 of feed cylinder F-cyl isretracted, switch SW3 is closed. Through SVB1 the bending cylinder B-cylis operated moving the piston rod 28 thereof downward from the positionshown in FIG. 1 to that shown in FIGS. 2 and 3.

As the piston rod 28 of the bending cylinder moves down, into contactwith the tube T and starts to bend the same, sliding plate will bepulled forwardly until it reaches the position of FIGS. 2 and 3 as thebend is finally completed.

As the plate 20 reaches this position the switch SW2 thereon istriggered by the adjustable stop 24. Through SVB2 the piston rod 28 ofthe bending cylinder B-cyl is caused to go up and through the togglelevers 29 and 30 the sliding plate 20 is returned to retracted position.Switch SW2 is closed by contact with adjustable contact 25, completingcircuit for next cycle. Through SVA2 the cylinders cyl-l, cyl-2 andcyl-3 are caused to open and the feed cylinder F-cyl is operated to movethe piston rod 7 thereof forwardly and the cycle is repeatedcontinuously until the entire tube or the like has been bent into azig-zag web as indicated at W.

The slot 34 is provided in the toggle lever 30 to permit the pivot pin35 to move upward in the slot as indicated in FIG. 12 when the pistonrod 28 of the bending cylinder starts to retract so that the groovedbending die 43 carried by the piston rod 28 Will not bind in the bend.

As the piston rod 28 continues to retract, the pivot pin 35 will bereceived in the notch 41 of the pick-up link 39 and the bending cylinderwill be swung to the angular position shown in FIG. 1 as the piston rod28 thereof is fully retracted.

Then as the piston rod 28 of the bending cylinder B-cyl is again moveddownward to form another bend in the tube, it will be guided by thepick-up link 39 so that the grooved die 43 thereon will contact the tubeat the proper point to make the next bend therein.

In the foregoing description certain terms have been used for brevity,clearness and understanding, but no unnecessary limitations are to beimplied therefrom beyond the requirements of the prior art, because suchwords are used for descriptive purposes herein and are intended to bebroadly construed.

Moreover, the embodiments of the improved construction illustrated anddescribed herein by way of example, and the scope of the presentinvention is not limited to the exact details of construction.

Having now described the invention or discovery, the construction, theoperation, and use of preferred embodiments thereof, and theadvantageous new and useful results obtained thereby; the new and usefulconstruction, and reasonable mechanical equivalents thereof obvious tothose skilled in the art, are set forth in the appended claims.

I claim:

1. Tube and bar-bending apparatus for forming a zigzag bent web member,comprising means for intermittently moving a tube and the likelongitudinally therethrough, a longitudinally slidable plate, a die uponsaid slidable plate located in the path of the tube and the like, asecond die located in the path of the tube and the like beyond the firstnamed die, said second die being mounted upon a longitudinally immovableportion of the apparatus, tube clamping means cooperating with saidsecond die, a bending die located between said first and second dies andmovable transversely across the path of the tube and the like, a pair oftoggle levers pivotally connected together and to the bending die at oneend, one toggle lever being pivotally connected at its other end to thesliding plate, the other toggle lever being pivotally connected at itsother end to said longitudinally immovable portion of the apparatus,means for moving the clamping means relative to the second die and meansfor moving the bending die transversely across the path of the tube andthe like to form successive V-shaped bends therein, one of said togglelevers having a longitudinal slot at the pivotal connection to thebending die to prevent binding of the tube upon retraction of thebending die.

2. Tube and bar-bending apparatus as defined in claim 1, in which themeans for intermittently moving a tube and the like longitudinallytherethrough includes a pneumatic feed cylinder.

3. Tube and bar-bending apparatus as defined in claim 2, in which thetube clamping means is operated by a pneumatic cylinder.

4. Tube and bar-bending apparatus as defined in claim 3, in which thesecond die is operated by a pneumatic cylinder.

5. Tube and bar-bending apparatus as defined in claim 4, in which thesecond die is located upon one arm of a bell-crank lever, and the otherarm of the bell-crank lever is pivotally connected to the piston rod ofsaid last named pneumatic cylinder.

6. Tube and bar-bending apparatus as defined in claim 1, in which aclamping die is located beyond and below the second die for successivelyclamping each lower bend in the zigzag bent web after said bend has beenformed by the bending die.

7. Tube and bar-bending apparatus as defined in claim 4, in which thebending die is operated by a pneumatic cylinder.

8. Tube and bar-bending apparatus as defined in claim 7, in which one ofthe toggle levers has a longitudinal slot at the pivotal connection tothe bending die, and in which the bending die cylinder is pivotallymounted.

9. Tube and bar-bending apparatus as defined in claim 8, in which apivoted pick-up link swings the bending die cylinder upon its pivot.

10. Tube and bar-bending apparatus as defined in claim 6, in which saidclamping die is located upon one arm of a bell-crank lever, and theother arm of the bell-crank lever is pivotally connected to the pistonrod of a pneumatic cylinder.

11. Tube and bar-bending apparatus as defined in claim 4, in which aclamping die is located beyond and below the second die for successivelyclamping each lower bend in the zig-zag bent Web after said bend hasbeen formed by the bending die, and in which the bending die is operatedby a pneumatic cylinder and the clamping die is operated by a pneumaticcylinder.

12. Tube and bar-bending apparatus as defined in claim 11, in which afour-way double-solenoid valve controls operation of the bending diecylinder, and a second four-way double-solenoid valve controls operationof all of the other cylinders.

13. Tube and bar-bending apparatus as defined in claim 5, in which thebell-crank lever is pivoted upon a transversely movable spring-biasedblock.

14. Tube and bar-bending apparatus as defined in claim 10, in which thebell-crank lever is pivoted upon a transversely movable spring-biasedblock.

15. Tube and bar-bending apparatus as defined in claim 12, in which thesolenoids of said valves :are located in an electric circuit, a firstlimit switch and a second limit switch in said circuit located on saidsliding plate, a third limit switch in said circuit located adjacent thefeed cylinder, means on the piston rod of the feed cylinder foralternately operating the first limit switch and the third limit switch,and a spaced pair of adjustable stops for operating the second limitswitch in opposite directions at opposite ends of the movement of thesliding plate.

16. Tube and bar-bending apparatus as defined in claim 1, in which thepivots for the other ends of the toggle levers are mounted upon sleevesadjustably mounted upon the levers.

References Cited UNITED STATES PATENTS 382,426 5/1888 Howe 72-3012,485,282 10/ 1949 Green 140-71 CHARLES W. LANHAM, Primary Examiner.

L. A. LARSON, Assistant Examiner.

1. TUBE AND BAR-BENDING APPARATUS FOR FORMING A ZIGZAG BENT WEB MEMBER,COMPRISING MEANS FOR INTERMITTENTLY MOVING A TUBE AND THE LIKELONGITUDINALLY THERETHROUGH, A LONGITUDINALLY SLIDABLE PLATE, A DIE UPONSAID SLIDABLE PLATE LOCATED IN THE PATH OF THE TUBE AND THE LIKE, ASECOND DIE LOCATED IN THE PATH OF THE TUBE AND THE LIKE BEYOND THE FIRSTNAMED DIE, SAID SECOND DIE BEING MOUNTED UPON A LONGITUDINALLY IMMOVABLEPORTION OF THE APPARATUS, TUBE CLAMPING MEANS COOPERATING WITH SAIDSECOND DIE, A BENDING DIE LOCATED BETWEEN SAID FIRST AND SECOND DIES ANDMOVABLE TRANSVERSELY ACROSS THE PATH OF THE TUBE AND THE LIKE, A PAIR OFTOGGLE LEVERS PIVOTALLY CONNECTED TOGETHER AND TO THE BENDING DIE AT ONEEND, ONE TOGGLE LEVER BEING PIVOTALLY CONNECTED AT ITS OTHER END TO THESLIDING PLATE, THE OTHER TOGGLE LEVER BEING PIVOTALLY CONNECTED AT ITSOTHER END TO SAID LONGITUDINALLY IMMOVABLE PORTION OF THE APPARATUS,MEANS FOR MOVING THE CLAMPING MEANS RELATIVE TO THE SECOND DIE AND MEANSFOR MOVING THE BENDING DIE TRANSVERSELY ACROSS THE PATH OF THE TUBE ANDTHE LIKE TO FORM SUCCESSIVE V-SHAPED BENDS THEREIN, ONE OF SAID TOGGLELEVERS HAVING A LONGITUDINAL SLOT AT THE PIVOTAL CONNECTION TO THEBENDING DIE TO PREVENT BINDING OF THE TUBE UPON RETRACTION OF THEBENDING DIE.